Rotary engine.



No. 806,399. PATENTBD DEC. 5, 190.5.

J. T. CUNNINGHAM.

ROTARY ENGINE. APPLIOATION FILED SEPT, 19. 1905.

4 SHEETS-SHEET I. 5

HU l fw WITNESSES.

N0. 806,399. PATENTED DEG. 5, 1905. J. T. CUNNINGHAM.

ROTARY ENGINE.

APPLICATION FILED SEPT. 19. 1905.

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. .UNITED N PATENT OFFICE.-

JoHN ir. CUNNINGHAM, OFALLEGHENY, PENNSYLVANIA.

` ROTARY ENGINE.

Specification of Letters Patent.

Application iiled September 19, 1905. Serial No. 279,129.

To all whom it may'concermv Be it known that I, JOHN T. CUNNINGHAM, a

resident of Allegheny, in the county of Allegheny and State- 4ofPennsylvania, have invented a new and useful Improvement in 1totaryEngines; and 1 do hereby declare thefollowing to be a full, clear, andexact description thereof.

My invention rel-ates to rotary engines; and

ythe object is to provide an engine of this type which is readilyreversible and which utilizes the motiveliuid-not only under pressure,but also under expansion, in practically the same manner as any ordinaryreciprocating engine.

Various'types of rotary engines have heretovfore been designed, the onesmost extensively in use bein@ what are -known as turbines These utilizethe blowing action of the fluidi .medium being employed and depend fortheir Athat the fluid medium entering the. cylinder will beautomatically governed or regulated and will be cut ofi' automaticallywhen it reaches the desired pressure, thus r maintaining a practical-lyuniform pressure againstthe vane.

`4A further feature consists in such an arrangement of inlet and exhaustports and Vvalves that a constantly-regulated pressure will bemaintained on one side of the vane and 1 the pressure continuously andcompletely exhausted-from the opposite side of the vane,

thus utilizing the full efiiciency of the pressure medium.

Another feature of the invention consists in so constructing theV enginethat it can be kreadily reversed and can be driven in either directionwith equal facility and efliciency.

y Otherfeatures of the invention will appear from the description andclaims hereinafter Theengine is adapted to any motive iiuid underpressure, suchas steam, compressed air, gases,` or the like. Y v .In theaccompanying drawings, Figure 1 is a transverse vertical sectionthrough. an engine constructed according to ymy .invention, the

yview of the main shaft and vane.

.or headsQ and 2f.

Fig. 2 is an end View of thesame. Fig. 3 is t a longitudinal verticalsection taken on the kline 3 3, Fig. 1. Fig. 4 is an inside view of onehead of the cylinder. Fig. 5 is an end Fig. 6 is a longitudinal sectionthrough the vane, taken .on the line 66, Fig. 1. Fig. 7 is a transverse-section through the vane and vane-hub, taken on the line 7'7, Fig.` 6.Fig. 8 is a perspectiveview of a valve member, the same being broken, toshow its cross-section. Fig. 9 is a similar view of the Valve-partition.Fig. 10 is a vertical section through a modication, showing threerotaryabutments. Fig. 11 is Patented Dec. 5, 1905.

l section being taken on the line 1-1, Fig. l3.

asimilar view showing four rotary abutments.

Fig. 12 is a vertical transverse section showing a modification havingone abutment. Fig., 13 is an inside View jof one of the cylinderheads of-this modification, and Fig. 14 is a similar view of the opposite head.

` Myengine is provided with a suitable caising or cylinder 1, providedwith end portions Mounted in this cylinder isthe main shaft 3, whichinside of the cylinder f `is enlarged or otherwise suitably providedwith a hub.v Mounted on or formed integral Vwith this hub is the vane 4,against which the pressure medium 'acts in order toproduce rotation ofthe shaft 3. Theshaft 3 extends through the heads of the cylinders andon one end will be provided with a suitable 'fly-wheel 5y and will alsobe provided with suitable means whereby itspower can be communicated tothe machine or machines to be driven. The opposite end of the shaftoutside of the cylinder-head is provided with a'gear-Wheel 6 for apurpose hereinafter to be described. y

With all engines, whether of the rotating or reciprocating type, it isnecessary that a stationary or substantially stationary abutment-beprovided, against which the pressure medium can back, and thus beenabled to drive or move the movable element or piston. y In my'enginethe vane 4 takes the place of the usual piston of a reciprocatingengine., One of the diiiiculties in constructing a proper rotary engineis to provide a suitable abutment or abutments located inopposition tothe-vane and against which the pressure medium will act,y which.abutment or abutments must be movable, so as togpermit the vane to IIOwith the main shaft or vane-hub and cut away, so as to permit the vaneto pass. As shown in Fig. 1, the engine is provided with two suchrotating abutments 7 and 8, which are identical in construction and'modeof operation. Each of thesehas a practically steamtight contact with themain shaft or vane-hub 3 and a similar fit in pockets or enlargements 9in the cylinder-casing. They are provided .with trunnions 10, which aresuitably jour- :naled in the heads Vof ythe main cylinder. Theseabutmentssare provided with cut-away portions 1:1 of the proper size andshape to permit the vane 4 to pass, but at the -sarne time maintainasubstantially steam-tight conitact. These abutments obviously mustrotate withther main shaft-3. y They may be rotated for this purpose inany suitable way and -by 'any suitable mechanism. I have shown for 'thispurpose'gears V12 on the ends of the trun- Vnions of-said abutments,which gears mesh `with vthe gear'6 on the ymain shaft 3. Ob- -viouslyvarious other mechanisms for this purpose may be used.

In order to maintain a constantpressure on one side of the vane 4 and aconstant exhaust from itsopposite side, it is-essential that the 'inletsand exhausts be th rough the ends of the mainshaft or 4vane-hub 3,'andthis is one of the important features of my engine. As `shown inthedrawings, the'controlling-valve -is'located-at the-top ofthecylinder; but this is a matter largely of choice. Theinductionpipe-isshown atf14-and'the exhaust-pipe at -1 5. These pipes lead tofafour-wayvalve 16, by

' meansof which the pressure medium may be directed'to'eitherside ofthe'vane 4 andthe engine readily reversed. From the casing of the valve16 ports 18 and 19 lead to the opposite heads of the-cylinder. :Each ofthese heads is providedon its inner face with an annular groove 20,vwhich grooves communi- 'cate the one with the port 18 and the'otherVwith the port 19. The main `vshaft or vane- `hub'3 is provided withtwoports'21 and 22, lone ofwhic'h opens out through one end of saidshaft,'while1the other opens `outthrough the-opposite end of saidshaft,said portsbe- Ling `in constant communicationwith the an- 'nulargrooves 20 in the heads ofthe cylinder, 'so that one of said ports isconstantly open 'to the admission of pressure medium, while the other isconstantlyopen 'to the atmosphere. One of theseports opens-through thewall of the main shaft or vane-hub on one side of the-vane4,'while theother port opens through-thewall ofsaidvshaft or vane-hub on theoppositeside offsaid vane.

The construction so far described willv produce ay rotary-enginecapableof efficient operation. I-prefer, howeverpto-provideautomatically-arranged means for controlling the pressure acting againstthe Vane 4. To this end the Vane-is cut out atits middle to pro- 4yidespace for` regulatingevalves. There are tight fit in 'the vane itself.

'iiuid pressure.

-two valves 23 and 24, which are exactly similar-and arranged to open onopposite faces of the vane. These valves are pivoted on a pintle 25andare provided at their ends with inwardly-projecting wings 26,' whichare of considerable width, as shown in Fig. 6. Also hinged on the pintle25 and lying between the valves 23 and 24 is the partition or diaphragm27, which is provided at its ends with wings 28, which lie just insidethe wings 26 on the valves. The meeting faces of the wings 26 and'28have aground lit, -sothat they work steam-tight on each other. The outerand lower faces of the wings 26 also have a-steam- As a consequence theai'ea on the inner faces of the valves 23 and 24, which is subject toHuidpressure, is between tliewings 26, while the entire outer faces ofsaid valves are subject to These valves are therefore differential,having a larger-area exposed to fluid pressure in the cylinder thantothe fluid-pressure entering through the port 21 or 22.

The'operation of the engine described is as follows: When the four-wayvalve 16 isin 'the-position indicatedinFig. 3, the pressure mediumwillpass by the port 18 into the annular groove 20 in theleft-hand head2of. the main cylinder, whence it will iiowthrougli `the port 21 intothechamber in the vane 4.

This-will cause the valve 23 on that side of the vane to open,permitting the pressure medium to pass into the main cylinder. :It willfill thespace between the vane and the movableabutment v7, thus forcingthe vanein the direction-of the'arrow'SO. As-soon as the pressure in thecylinder has-reached thedesired degree the yvalve 23 will automaticallyclose by reason of having an increased area exposed toeylinder-pressure, thus -preventing further pressure medium fromenteringthe cylinder. As soon, however,A as thepressure falls materially byreason of expansion and'exhaust and a'balance is-established the Valve23 will again automatically open and permit more live pressure medium toenter the cylinder. In this manner the pressure in vthe cylinder isautomatically lregulated and fact that the'pressure behind the valve 23will force the diaphragm 27 toward the valve V24, so that the vwings 28on said diaphragm will'contact with'the valve 24 and unseatitlie latter.Hence this side of the vane will be in constant opencommunicationthrough the lport 22, annular groove 2O in the right-hand head 2a of themain cylinder, and port 19 TOO IOS i IIO:

soeces v Y"with the exhaust-pipe 15.v As a' consequenceall the pressureon that side of the vane will 'be removed and the fullest eiiciency ofthe uid'medium will be secured. `As thevane.

moves in the-direction of the arrow 30 it will turn the main Shaft orvane-hub 3 in'the same direction, and through the gearing described theabutments 7 and 8 will berotated in unison therewith. The end of thevane will reach the point 31 at the casing practically'at the same timethat'the edge 32 of the abutment 8 reaches the same point, and in thefurther rotation of thel parts the vane will sweep through the cut-awayportion 11 of the 1 abutment, maintaining constantly a practicallysteam-tight joint. Bythe time the 'end of the v has been rotating in thedirection of the arrow 34; but at no time has it opened anycommunication between the two opposite sides of theV vane. As aconsequence these rotating elements act as abutments for the-pressureme.-

diumv in order to permit the latter to exert its i pressure on the vaneand at the same time act to prevent any of the livefiuid escaping aroundto that side of the vane whichis in communication with the exhaust. Itwill thus be seen that the arrangement provides a constant regu-y lationof pressure on one side of the vane and a constant and complete exhaustfrom theopposite side of the vaneand without any chance of permittingwastage of. live pressure medium. To reverse the engine, the valve l16will be given a quarter-turmjso as to directy the pressure mediumthrough the port 19 into the annular groove 2O in the right-hand head 2tof the cylinder and thence through the into the cylinder.

port- 22 under the valve 24 in the vane and On the opposite side of thevane the cylinder will be open through the valve 23, port 21, annular'groove 20 in the head 2, and port 18 to the atmosphere. As aconsequence the engine will'be driven in the opposite direction. Sincethe valves 23 and 24 on the opposite `sides of the vane are identical inconstruction .and arrangement, the vane4 can be driven in eitherdirection with equal facility.

The number of rotating abutments may be varied to suit convenience or tomeet special conditions.- In Figl 10 is shown a modification in whichthere are three rotating abutments; but these are constructed andoperated in precisely the same manner as the two abutments shown in Fig.l, and the engine is also i the same in all other particulars. Fig. 1l

shows precisely the same engine with four rol tating abutments.

and in this modification it is necessary to slightly change theadmission and exhaust grooves 20- in the heads of the cylinder.

These grooves instead of being full circles, as in the othermodifications, are interrupted, as at 36, so that there is a slightperiod during the rotation of the main shaft in which the main cylinderis not in communication with. the source of pressure medium. This isnecessary because with the single rotating abutment shown the live fluidwould be placed in communication with 'the exhaust side of the vrvanevduring a certain portion of the rotation of the abutment. This wouldresult in waste of pressure medium, and in order to prevent l this thegrooves 20 are interrupted in the manner described,- so as to lshut offthe inlet for a portion of the revolution of the main shaft. Both of thegrooves are'similarly interrupted, so that the' engine can be driven inyeither direction withoutwasting pressure medium.l

The engine described can be compounded to any desired degree. This canbe done by connectingto the main shaft3 other vanes working in cylindersof progressively-increasing size and conducting the pressure 'mediumthrough-these chambers 1n successlon. r When compounding with the formhaving 'only a single abutment, it will not be `necessary to interruptthe grooves 20, as any pressure mebe utilized in thenext cylinder.

1. In a rotary engine, the combination of a chamber or casing, arotating shaft or hub therein, a vane on said shaft, a rotating abutmenthaving contact with the shaft and lcut away to permit the vane to passthe same, an inlet through one head of the chamber, an outlet throughthe opposite head of the chamber, said inlet and outlet terminatinginannularl grooves on the inner faces of said head, and ports opening atthe ends of the shaft and `diumescaping in one cylind er' willnecessarily IOO registering with said annular grooves, one of IIO IZO

side of the vane, and a valve controlling the inlet, said valve beingcontrolled automaticf ally by the pressure in the cylinder and arrangedto maintain such pressure substantially constant. Y t

3. In a rotary engine, the combination of a chamber, a rotating shaft orhub therein, av vane on said shaft, a rotating abutment having contactwith said shaft and cut away to permit thevane to passthe same, an inlett0 one side of said vane, an exhaust from the opposite side of the vane,and a differential `Valve controlling the inlet-port.

4. In a rotary engine, the combination of a chamber or cylinder, arotating shaft or hub therein, a vane on said shaft, arotatingabutmenthaving Contact with said shaft and eut away to permit the vane to passthe same, said shaft having ports opening on opposite sides of the vaneand leading out through the ends of the shaft to fluid supply andexhaust connections, and differential valves controlling the openings onboth sides of the vane zand arranged to open outwardly.

' 5. In a `rotary engine, theeombination of a chamber, or easing, a.rotating shaft or hub therein, a vane on said shaft, a rotatingabutment having eontaet with the shaft and eut away to permit the vaneto pass the same, said shaft having passages therethrough opening onopposite sides of the vane and having Colnmunieation with Huid supplyand exhaust conneetions, differential valves controlling said openingson both sides of the vane and eaeh comprising a valve opening outwardlyand havinga greater area exposed to the cylinderpressure than to theinlet-pressure, and a movable partition or diaphragm between said valvesand having projections arranged to eontaet therewith.

7. In a rotary engine, the combination of a eharnber or Cylinder, arotating shaft or hub therein, a vane on said shaft, a plurality ofrotating abutments eaeh having Contact with the shaft and being eut awayto permit the vane to pass the same, supply and exhaust portsCommunicating with annular grooves in the inner faees of thecylinder-heads, and ports in the main shaft opening at the ends thereofand communicating with said annular grooves and opening respectively onopposite sides of the vane.

In testimony whereof I, the said JOHN 'I`. CUNNINGHAM, have hereunto setmy hand.

JOHN T. CUNNINGHAM.

Witnesses:

MARGARET C. KEEBLE, F. W. WINTER.

